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铁虫 (小有名气)

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[求助] 各位合成大神们，求指点已有1人参与

大家好！我想咨询下利用油酸和稀土氯化物为原料来合成上转换纳米粒子的相关问题。
我参考的文献是一篇 nanoscale ，原文合成步骤如下：
First, lanthanide oleate (Ln(oleate)3,Ln=Y, Yb, and Er/Tm) complexes were prepared by adapting the synthesis method for preparing the iron oleate complex to synthesize UCNPs. For the green-emitting UCNPs, 0.8mmol YCl3.6H2O, 0.18mmol YbCl3.6H2O, 0.02mmol ErCl3.6H2O, and 3.1mmol sodium oleate were loaded into a three-necked flask containing a solvent mixture of deionized (DI) water (3ml), ethanol (3.5ml) and hexane (7ml). The reaction solution was heated to 70℃ heating for 4h, the synthesized Ln(oleate)3 complexes (Ln=Y, Yb, and Er) were washed three times with DI water. These complexes were then mixed with OA and ODE in which the ratio of OA to ODE varied from 0:21 to 21:0 to investigate the effect of OA on the size and morphology of the UCNPs. The mixture was heated to 150℃ to form a transparent solution. After cooling to 50℃, 10ml of a methanol (MeOH) solution containing NaOH (2.5mmol) and NH4F (4mmol) was added to the reaction flask. The mixture was stirred for 40 min and then the MeOH was removed. Finally, the reaction mixture was heated to 320℃ at a rate of 15℃/min and maintained for 90 min under a protective Ar atmosphere. The synthesized NCs were washed several times with ethanol and then dispersed in hexane.
翻译成中文大概如下：
1. 三口瓶中加入3 ml的去离子水，3.5 ml乙醇和7 ml 己烷；
2. 0.8 mmol 的YCl3.6H2O，0.18 mmol 的YbCl3.6H2O，0.02 mmol 的ErCl3.6H2O，3.1 mmol 的油酸钠加入上述三口瓶中；
3. 加热到70℃，保温4 h之后，冷凝回流，取上层油状物质，用去离子水清洗三遍；
4. 将上述得到的油酸复合物与一定比例的油酸OA和十八烯ODE（OA:ODE= 19:2，总共21 ml）混合；加热上述混合物到150℃形成透明的溶液（保温40分钟）；
5. 冷却到50℃,10ml甲醇溶液（包含2.5mmol的NaOH和4mmol的NH4F）加入到三口瓶中，维持搅拌40 min, 搅拌去除甲醇；
6. 升温到320℃,15℃/min的速度，保持90min，氩气保护；
7. 离心分离得到样品，用乙醇清洗数遍，保存在己烷中；为何会有絮状沉淀，根本不分散到溶剂中。
小弟有几个问题，希望大家帮我解答下。
Q1: 1-3步合成稀土油酸盐的步骤中，第三步合成出的那个分层的稀土油酸盐怎么个取法？直接从三口瓶中倒出来还是怎样？倒出来在那个烧瓶壁上面会粘好多，我试过。其他文献有说分液漏斗分液的，还是要倒出来，损失不可忽略。
Q2: 第五步的10ml甲醇溶液（包含2.5mmol的NaOH和4mmol的NH4F）是要立刻配制然后加入吗？
Q3: 第六步的升温到320度，我的不知道怎么都升不到320度，我设置的是320度，就是到了314度就上不去了，不知道为何？
Q4: 第七步的离心分离得到样品，用乙醇清洗数遍，保存在己烷中；为何会有絮状沉淀，根本不分散到溶剂中？
Q5: 温度较高时候就会在反应烧瓶中冒白烟，好恐怖的感觉，白烟是为何呢？
初次采用这种方法合成，多有不懂，忘多指教啊？

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